The present invention relates to a heat exchanger preferably used as an evaporator of a car air conditioner, which is a refrigeration cycle to be mounted on, for example, an automobile, and a method of manufacturing the same.
Herein and in the appended claims, the left-hand and right-hand sides of FIG. 2 will be referred to as “left” and “right,” respectively.
Conventionally, a so-called laminated evaporator has been widely employed as an evaporator for use in a car air conditioner. In the laminated evaporator, a plurality of flat, hollow members, each of which includes a pair of depressed plates facing each other and brazed to each other at their peripheral edge portions, are arranged in parallel, and corrugate fins are each disposed between and brazed to the adjacent flat, hollow members.
However, in recent years, evaporators have been demanded to further reduce size and weight and to exhibit higher performance. The present applicant proposed a heat exchanger for use in an evaporator which fulfills those requirements (refer to Japanese Patent Application Laid-Open (kokai) No. 2005-164226). The proposed heat exchanger includes a heat exchange core section, a first header section, a second header section, a third header section, and a fourth header section. The heat exchange core section includes a plurality of rows of heat exchange tube groups arranged in an air flow direction, each heat exchange tube group consisting of a plurality of heat exchange tubes arranged in a left-right direction at predetermined intervals; a plurality of corrugate fins disposed between and joined to the adjacent heat exchange tubes and disposed on the outer sides of and joined to the leftmost and rightmost heat exchange tubes; and two side plates disposed on the outer sides of the leftmost and rightmost corrugate fins, respectively, and joined thereto. The first header section is disposed on a first-end side of the heat exchange tubes, and the heat exchange tubes of at least a single heat exchange tube group are connected thereto. The second header section is disposed on the first-end side of the heat exchange tubes and upstream of the first header section with respect to the air flow direction, and the heat exchange tubes of the remaining heat exchange tube group(s) are connected thereto. The third header section is disposed on a second-end side of the heat exchange tubes, and the heat exchange tubes connected to the first header section are connected thereto. The fourth header section is disposed on the second-end side of the heat exchange tubes, and the heat exchange tubes connected to the second header section are connected thereto. The first and second header sections include two hollow header section bodies whose left and right ends are open, and two caps which are joined to left and right end portions of the two header section bodies while bridging the left end portions and the right end portions, respectively, thereby closing openings of the left and right ends of the two header section bodies. The third and fourth header sections include two hollow header section bodies whose left and right ends are open, and two caps which are joined to left and right end portions of the two header section bodies while bridging the left end portions and the right end portions, respectively, thereby closing openings of the left and right ends of the two header section bodies.
The heat exchanger disclosed in the above publication is manufactured through steps of assembling and provisionally joining the respective constituent members, and brazing all the constituent members together. Specifically, this heat exchanger is manufactured through steps of arranging the heat exchange tubes, the corrugate fins, and the header section bodies in an assembled condition; provisionally joining the constituent members, while the caps are arranged in such a manner as to bridge end portions of the header section bodies on opposite sides of the header section bodies, and the side plates are arranged, independently of the caps, on the outer sides of the leftmost and rightmost corrugate fins; and simultaneously brazing the heat exchange tubes and the corrugate fins together, the heat exchange tubes and the header section bodies together, the header section bodies and the caps together, and the corrugate fins and the side plates together.
However, manufacturing the heat exchanger disclosed in the above publication involves difficulty in arranging the side plates at respectively predetermined positions.